A General Clinical Research Center for children is being operated in the Children's Hospital. Patients in the Center are primarily children and any qualified individual in the Medical Center Complex may use the facility provided an adequate protocol is presented. Patients with glycogen storage disease, infantile hypoglycemia, lysosomal dieases, malabsorption syndromes in children, leukemia, persistent glomerulonephritis, cholesterol ester storage disease with familial cirrhosis, growth retardation, systemic hypertension in childhood, Reye's syndrome, hypobetalipoproteinemia, intractable diarrhea, vitamin D deficiency and vitamin D resistant rickets, cardiac function in post-operative coarctation of the aorta, fructose-1-phosphate aldolase deficiency, and late infantile hypocalcemia have been studied in the past year.